>> Can you see a similar "easy" way to something like this with
>> 2 different "oscillator" signals [ie, PIC_pin+diode -vs- bulky
>> external switching logic]?
>>
>> I want to use one of the programmable oscillator chips - namely
>> the ECS-300, which has divide ratios from 1/2 down to 1/256 - but
>> unfortunately the non-divided output comes off a different pin
>> from the divided output, so you still need a way to select
>> between the two signals. All in all, with this part, you can get
>> 20Mhz, 10, 5, 2.5, ............, or 16Mhz, 8, 4, 2, 1, .5, .25,
>> ........... - nice.
>
>
>Hi Dan, yeah, here is a circuit that will do what you ask,
>it needs two PIC pins driven differentially.
>I am not too proud of this circuit, although it might
>be cheaper and smaller board footprint than using logic
>gates for switching it is not very pretty. I think it should
>be functional though, even with 1N4148s.

Hi Roman, a variation on the old AND-OR logic, I see.
Good start. The series Rs at 10K would probably be too big
for 20 Mhz operation - 2-3K might be alright.

Do you really need the pull-up diodes to the pins? Why not
just float vs pull low.